Crop & Pest Report

Accessibility


| Share

Grasshopper Feeding During Cool Temperatures (09/10/20)

Grasshoppers are cold-blooded organisms like all insects and require warm temperatures to feed and do other biological activities, such as egg laying. When the weather turns cold, overcast or rainy, grasshoppers need to warm up their body temperatures by basking in the sun for several hours during the morning before feeding.

Grasshoppers ent.1are cold-blooded organisms like all insects and require warm temperatures to feed and do other biological activities, such as egg laying. When the weather turns cold, overcast or rainy, grasshoppers need to warm up their body temperatures by basking in the sun for several hours during the morning before feeding. Some species of grasshoppers will turn their body sideways or perpendicular to the rays of sunlight or climb up to the top of a plant. Others will bask in open bare spots on the ground. Grasshopper prefer temperatures of 68 to 100 F for feeding and most feeding occurs during the warmer periods and hotter days. As our temperatures have started to decrease in September, grasshoppers will be feeding less and causing less damage to any later maturing field crops. Growers should take this into account before making any treatment decision when adult grasshopper populations are still fairly high in late maturing crops (see IPM Grasshopper map).

Grasshoppers lay eggs in the fall, and prefer air temperatures above 66F for egg laying. When fall arrives early and is cooler than normal, this shortens the time for egg laying and decreases the impact for high levels of future grasshopper populations. In contrast, warm, late falls will encourage a long egg laying period and favor conditions for increasing grasshopper populations.

 

Janet J. Knodel

Extension Entomologist

 

This site is supported in part by the Crop Protection and Pest Management Program [grant no. 2017-70006-27144/accession 1013592] from the USDA National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed are those of the website author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.

USDA logo

Creative Commons License
Feel free to use and share this content, but please do so under the conditions of our Creative Commons license and our Rules for Use. Thanks.